Aims: The aim of this project is to examine the role of environmental, dietary and genetic factors in determining the risk of developing asthma and chronic bronchitis in a cohort of over 50,000 older adults of Chinese ethnicity in Singapore. There is clear evidence of a role for genetic factors in asthma, evidence for chronic bronchitis is mounting. However, there are few prospective data to address these issues. The possible protective role of diet, including intake of micronutrient antioxidants, as well as the role of macronutrient and caloric balance is of increasing interest but prospective data are essential to examine these associations in an unbiased manner. Procedures and techniques: To do this, we have expanded the scope of a cohort established to examine the relation between diet and cancer. This NCI-funded study includes detailed dietary information using a questionnaire developed for and validated in this population. Follow-up, funded by NCI, includes a telephone interview followed by collection of blood and urine. To expand the capability of the cohort to the study of chronic bronchitis and asthma, we added questions on these entities to the follow-up. In addition, smoking and environmental tobacco smoke data has been expanded. Over the next 4 years as follow-up of the cohort is completed, we will be able to conduct epidemiologic analyses to examine risk factors and modifiers for nonmalignant respiratory disease in adults. Genetic polymorphisms for these conditions can be examined in nested case-control samples. This population is of particular interest because the Chinese women in Singapore and elsewhere have been reported to have high rates of chronic bronchitis in the face of low levels of smoking. The reason for this pattern is unknown. This Chinese population also has high intake of micronutrients that may modify the risk of lung disease. Accomplishments: The follow-up of the cohort is underway. The follow-up questionnaire with our new nonmalignant respiratory disease outcome questions has been administered to 18,000 subjects. We have received this partial dataset and have begun preliminary analyses. We anticipate being able to write manuscripts in FY2002 when the number of subjects enrolled will provide adequate study power for analysis of risk factors for new onset symptoms.